[thrance]

You can, in principle, formalize any correct mathematical proof and verify its validity procedurally with a "simple" algorithm, that actually exists (See Coq, Lean...). Coming up with the proof is much harder, and deciding what to attempt to prove even harder, though.

[AlotOfReading]

You can verify it with a simple algorithm, but that verification won't always be cheap. If it was, curry-howard would be incredibly uninteresting. It only seems cheap because we usually have little interest in exploring the expensive theorems. Sometimes we do though and get things like the 4 color theorem whose proof verification amounts to combinatorial search.